I tried to side-install the Android 2.2 version of "Audiopo" (an app to play mp3 files at a different speed), on a rooted Sony PRS-T1, via Total Commander. TC opened the APK and told me the permissions needed, but then when I clicked "install" it first showed a progress bar and then failed, said "app not installed" but did not say why. There are still 15 megabytes of space in the apps area. (Not much, I know, but this is small app...) What's going on?

Note that this is different behavior than when I've tried to install apps that are for later versions of Android, then Total Commander says "problem parsing app" and never gets to the permissions list.

But _why_ is it having trouble? Can another file manager possible do better on installing the same APK? The APK is supposedly made for Android 2.2, the version running on the PRS-T1. I have managed to install and run a couple of other audio speed changing apps, but they have other issues: invisible folder and file names (e-ink display issue), and incorrect playing of mono mp3 files (not a PRS-T1 issue). But they did install.

I tried one more thing: using a command line to install it. Opened "terminal emulator" (busybox) and used the command "pm install apkpathname". It ran for a second and then printed one word as a result: